To just run a command as admin in a non-elevated Powershell, you can use Start-Process directly, with the right options, particularly -Verb runas.
It's a lot more convoluted than sudo, particularly because you can't just re-use the previous command with an additional option. You need to specify the arguments to your command separately.
Here is an example, using the route command to change the gateway :
This fails because we are not in an elevated PS:
> route change 0.0.0.0 mask 0.0.0.0 192.168.1.3
The requested operation requires elevation.
This works after accepting the UAC:
> Start-Process route -ArgumentList "change 0.0.0.0 mask 0.0.0.0 192.168.1.3" -Verb runas
Or for a command that requires cmd.exe:
> Start-Process cmd -ArgumentList "/c other_command arguments ..." -Verb runas
